1 | /* |
2 | * Copyright (c) 1985, 1993 |
3 | * The Regents of the University of California. All rights reserved. |
4 | * |
5 | * Redistribution and use in source and binary forms, with or without |
6 | * modification, are permitted provided that the following conditions |
7 | * are met: |
8 | * 1. Redistributions of source code must retain the above copyright |
9 | * notice, this list of conditions and the following disclaimer. |
10 | * 2. Redistributions in binary form must reproduce the above copyright |
11 | * notice, this list of conditions and the following disclaimer in the |
12 | * documentation and/or other materials provided with the distribution. |
13 | * 4. Neither the name of the University nor the names of its contributors |
14 | * may be used to endorse or promote products derived from this software |
15 | * without specific prior written permission. |
16 | * |
17 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
27 | * SUCH DAMAGE. |
28 | */ |
29 | |
30 | /* |
31 | * Portions Copyright (c) 1993 by Digital Equipment Corporation. |
32 | * |
33 | * Permission to use, copy, modify, and distribute this software for any |
34 | * purpose with or without fee is hereby granted, provided that the above |
35 | * copyright notice and this permission notice appear in all copies, and that |
36 | * the name of Digital Equipment Corporation not be used in advertising or |
37 | * publicity pertaining to distribution of the document or software without |
38 | * specific, written prior permission. |
39 | * |
40 | * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL |
41 | * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES |
42 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT |
43 | * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL |
44 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
45 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS |
46 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS |
47 | * SOFTWARE. |
48 | */ |
49 | |
50 | /* |
51 | * Portions Copyright (c) 1996-1999 by Internet Software Consortium. |
52 | * |
53 | * Permission to use, copy, modify, and distribute this software for any |
54 | * purpose with or without fee is hereby granted, provided that the above |
55 | * copyright notice and this permission notice appear in all copies. |
56 | * |
57 | * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS |
58 | * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES |
59 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE |
60 | * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL |
61 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
62 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS |
63 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS |
64 | * SOFTWARE. |
65 | */ |
66 | |
67 | #include <sys/types.h> |
68 | #include <sys/param.h> |
69 | #include <netinet/in.h> |
70 | #include <arpa/nameser.h> |
71 | #include <ctype.h> |
72 | #include <resolv.h> |
73 | #include <stdio.h> |
74 | #include <string.h> |
75 | #include <unistd.h> |
76 | |
77 | /* |
78 | * Expand compressed domain name 'comp_dn' to full domain name. |
79 | * 'msg' is a pointer to the beginning of the message, |
80 | * 'eomorig' points to the first location after the message, |
81 | * 'exp_dn' is a pointer to a buffer of size 'length' for the result. |
82 | * Return size of compressed name or -1 if there was an error. |
83 | */ |
84 | int |
85 | dn_expand(const u_char *msg, const u_char *eom, const u_char *src, |
86 | char *dst, int dstsiz) |
87 | { |
88 | int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); |
89 | |
90 | if (n > 0 && dst[0] == '.') |
91 | dst[0] = '\0'; |
92 | return (n); |
93 | } |
94 | libresolv_hidden_def (dn_expand) |
95 | |
96 | /* |
97 | * Pack domain name 'exp_dn' in presentation form into 'comp_dn'. |
98 | * Return the size of the compressed name or -1. |
99 | * 'length' is the size of the array pointed to by 'comp_dn'. |
100 | */ |
101 | int |
102 | dn_comp(const char *src, u_char *dst, int dstsiz, |
103 | u_char **dnptrs, u_char **lastdnptr) |
104 | { |
105 | return (ns_name_compress(src, dst, (size_t)dstsiz, |
106 | (const u_char **)dnptrs, |
107 | (const u_char **)lastdnptr)); |
108 | } |
109 | libresolv_hidden_def (dn_comp) |
110 | |
111 | /* |
112 | * Skip over a compressed domain name. Return the size or -1. |
113 | */ |
114 | int |
115 | dn_skipname(const u_char *ptr, const u_char *eom) { |
116 | const u_char *saveptr = ptr; |
117 | |
118 | if (ns_name_skip(&ptr, eom) == -1) |
119 | return (-1); |
120 | return (ptr - saveptr); |
121 | } |
122 | libresolv_hidden_def (dn_skipname) |
123 | |
124 | /* |
125 | * Verify that a domain name uses an acceptable character set. |
126 | */ |
127 | |
128 | /* |
129 | * Note the conspicuous absence of ctype macros in these definitions. On |
130 | * non-ASCII hosts, we can't depend on string literals or ctype macros to |
131 | * tell us anything about network-format data. The rest of the BIND system |
132 | * is not careful about this, but for some reason, we're doing it right here. |
133 | */ |
134 | #define PERIOD 0x2e |
135 | #define hyphenchar(c) ((c) == 0x2d) |
136 | #define underscorechar(c) ((c) == 0x5f) |
137 | #define bslashchar(c) ((c) == 0x5c) |
138 | #define periodchar(c) ((c) == PERIOD) |
139 | #define asterchar(c) ((c) == 0x2a) |
140 | #define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \ |
141 | || ((c) >= 0x61 && (c) <= 0x7a)) |
142 | #define digitchar(c) ((c) >= 0x30 && (c) <= 0x39) |
143 | |
144 | #define borderchar(c) (alphachar(c) || digitchar(c)) |
145 | #define middlechar(c) (borderchar(c) || hyphenchar(c) || underscorechar(c)) |
146 | #define domainchar(c) ((c) > 0x20 && (c) < 0x7f) |
147 | |
148 | int |
149 | res_hnok(const char *dn) { |
150 | int pch = PERIOD, ch = *dn++; |
151 | |
152 | while (ch != '\0') { |
153 | int nch = *dn++; |
154 | |
155 | if (periodchar(ch)) { |
156 | (void)NULL; |
157 | } else if (periodchar(pch)) { |
158 | if (!borderchar(ch)) |
159 | return (0); |
160 | } else if (periodchar(nch) || nch == '\0') { |
161 | if (!borderchar(ch)) |
162 | return (0); |
163 | } else { |
164 | if (!middlechar(ch)) |
165 | return (0); |
166 | } |
167 | pch = ch, ch = nch; |
168 | } |
169 | return (1); |
170 | } |
171 | libresolv_hidden_def (res_hnok) |
172 | |
173 | /* |
174 | * hostname-like (A, MX, WKS) owners can have "*" as their first label |
175 | * but must otherwise be as a host name. |
176 | */ |
177 | int |
178 | res_ownok(const char *dn) { |
179 | if (asterchar(dn[0])) { |
180 | if (periodchar(dn[1])) |
181 | return (res_hnok(dn+2)); |
182 | if (dn[1] == '\0') |
183 | return (1); |
184 | } |
185 | return (res_hnok(dn)); |
186 | } |
187 | |
188 | /* |
189 | * SOA RNAMEs and RP RNAMEs can have any printable character in their first |
190 | * label, but the rest of the name has to look like a host name. |
191 | */ |
192 | int |
193 | res_mailok(const char *dn) { |
194 | int ch, escaped = 0; |
195 | |
196 | /* "." is a valid missing representation */ |
197 | if (*dn == '\0') |
198 | return (1); |
199 | |
200 | /* otherwise <label>.<hostname> */ |
201 | while ((ch = *dn++) != '\0') { |
202 | if (!domainchar(ch)) |
203 | return (0); |
204 | if (!escaped && periodchar(ch)) |
205 | break; |
206 | if (escaped) |
207 | escaped = 0; |
208 | else if (bslashchar(ch)) |
209 | escaped = 1; |
210 | } |
211 | if (periodchar(ch)) |
212 | return (res_hnok(dn)); |
213 | return (0); |
214 | } |
215 | |
216 | /* |
217 | * This function is quite liberal, since RFC 1034's character sets are only |
218 | * recommendations. |
219 | */ |
220 | int |
221 | res_dnok(const char *dn) { |
222 | int ch; |
223 | |
224 | while ((ch = *dn++) != '\0') |
225 | if (!domainchar(ch)) |
226 | return (0); |
227 | return (1); |
228 | } |
229 | libresolv_hidden_def (res_dnok) |
230 | |
231 | /* |
232 | * This module must export the following externally-visible symbols: |
233 | * ___putlong |
234 | * ___putshort |
235 | * __getlong |
236 | * __getshort |
237 | * Note that one _ comes from C and the others come from us. |
238 | */ |
239 | void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); } |
240 | libresolv_hidden_def (__putlong) |
241 | void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); } |
242 | libresolv_hidden_def (__putshort) |
243 | u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); } |
244 | u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); } |
245 | |
246 | |
247 | #include <shlib-compat.h> |
248 | |
249 | #if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2) |
250 | # undef dn_expand |
251 | weak_alias (__dn_expand, dn_expand); |
252 | #endif |
253 | |